Cervical collagen concentration within 15 months after delivery

Trajectory of Postpartum Cervical Remodeling in Women Delivering Full-Term and Spontaneous Preterm: Sensitivity to Quantitative Ultrasound Biomarkers

OBJECTIVE

Women with a history of spontaneous preterm birth (sPTB) face an increased risk of recurrence. Yet, the factors contributing to the increased risk are unknown, hampering the development of targeted interventions. Noninvasive quantitative ultrasound (QUS) has been validated in the characterization of cervical tissue and has the potential to provide information about postpartum cervical remodeling. The objective of this study was to determine the postpartum cervical remodeling trajectories of women over 12 mo post-delivery and to determine whether there were differences between women who delivered full-term and spontaneous preterm that were sensitive to QUS biomarkers.

METHODS

Data were collected prospectively from 55 women: 41 who delivered full-term and 14 who delivered spontaneously preterm at 6 wk, 3, 6, 9 and 12 mo (±2 wk) postpartum. Data from QUS biomarkers: Attenuation Coefficient; Backscatter Coefficient; Shear Wave Speed; and Lizzi-Feleppa Slope, Intercept and Midband were analyzed from the acquired radiofrequency data using a Siemens S2000 ultrasound system with a transvaginal MC 9-4 MHz probe. The biomarkers were analyzed using descriptive statistics and linear mixed-effects models.

RESULTS

QUS biomarkers, Backscatter Coefficient and Lizzi-Feleppa Intercept showed significant differences during the year after delivery between women who had a full-term birth and sPTB (p < 0.05), suggesting that there are differences in the cervical remodeling trajectories between the two groups. All QUS biomarkers demonstrated significant variations between the full-term birth and sPTB groups over time (p < 0.05), indicating ongoing cervical remodeling for both groups during the 12-mo postpartum period.

CONCLUSION

QUS biomarkers identified cervical microstructure differences and trajectories in the year after delivery between women who delivered full-term and spontaneous preterm.

Perinatal Loss: The Impact on Maternal Mental Health

Importance

Psychological reactions to perinatal loss, although often self-limited, may lead to significant psychological morbidities. Obstetrician-gynecologists and other maternal health providers play a key role in recognizing the range of psychological responses to perinatal loss and providing education, support, and treatment options to their patients.

Objective

This review aims to define psychological reactions associated with perinatal loss, examine psychotherapy and psychopharmacologic treatments for psychiatric morbidities, discuss interpregnancy interval following perinatal loss, and highlight brief, psychological interventions that can be implemented by maternal health providers.

Evidence Acquisition

Search terms "perinatal loss psychology," "reproductive loss grief," "perinatal psychopharmacology," "psychopharmacology grief," and "interpregnancy interval" were utilized to search PubMed, Google Scholar, and PsycINFO.

Results

Grief is an expected, normal response to perinatal loss. Psychological morbidities, including major depressive disorder, generalized anxiety disorder, and posttraumatic stress disorder, are also associated with perinatal loss. Risk factors for these conditions include history of a psychiatric illness, childlessness, unknown cause of perinatal loss, limited social support, and marital/relationship discord. Careful interviewing and brief screening measures can help identify patients who may suffer from depressive or anxiety disorders following reproductive loss. Patients with perinatal loss can benefit from psychological and possibly pharmacologic treatments. Recommended interpregnancy interval after perinatal loss should be customized by gestational age and cause of loss.

Conclusions and Relevance

Patients with perinatal loss emotionally benefit from their reproductive health care providers acknowledging the psychological aspects of reproductive loss, inquiring about their emotional needs, and providing information regarding grief and mental health referrals.

Cesarean scar thickness in non-pregnant women as a risk factor for uterine rupture

Introduction: Whether there is an association between residual myometrial thickness (RMT) after cesarean section (CS) and the risk of uterine rupture (UR) or uterine scar dehiscence at the subsequent delivery has been sparsely investigated.Materials and methods: Our cohort included 149 women with a first CS in whom we measured RMT by transvaginal ultrasonography 6-15 months after their delivery. We did a follow-up study on delivery outcomes in the women's subsequent births. The exposure was scar measurements in the non-pregnant uterus, and the primary outcome was a diagnosis of UR or dehiscence. We calculated likelihood ratios (LRs) with 95% confidence intervals of having UR or dehiscence with a thin RMT (<3 mm).Results: Among the 149 women, 39 had a repeat CS (14 scheduled and 25 unscheduled procedures), and within these, we found one woman with UR and five women with uterine dehiscence. The proportion of women with a thin RMT was significantly higher among cases (4/6) than in controls (4/33); the LR was 5.5 (95% CI 1.9-16.2).Conclusions: The results suggest a significant association between a thin RMT as measured by transvaginal ultrasonography in the non-pregnant uterus after a first scheduled CS and the risk of UR or dehiscence at a subsequent delivery.

Short interpregnancy interval increases the risk of preterm premature rupture of membranes and early delivery

OBJECTIVES

Preterm premature rupture of membranes (PPROM) is a major contributor to overall preterm birth (PTB) rates. A short interpregnancy interval (IPI) is a well-known risk factor for PTB. It is unknown if a short IPI specifically affects the risk of developing PPROM in a subsequent pregnancy. We sought to determine the association between IPI and the risk of PPROM in a subsequent pregnancy.

METHODS

A retrospective cohort study using the Missouri birth certificate database of singleton births from 2003 to 2013 was conducted. A short IPI (delivery of the prior pregnancy to conception of the index pregnancy) was defined as ≤6 months. IPI >6 months was categorized into two groups: IPI 7-23 months and IPI ≥24 months. PPROM was defined as premature rupture of membranes between 16⁰ and 36⁶ weeks. Multivariable logistic regression was conducted to determine the association between IPI and PPROM while controlling for maternal age, race, body mass index (BMI), education level, use of social services (Medicaid insurance, food stamps, or participation in the WIC [Women, Infants, and Children] program), tobacco use, and history of PTB. Secondary outcome included the gestational age at delivery, categorized into five subgroups (≤24⁰, 24¹-28⁰, 28¹-32⁰, 32¹-34⁰, and 34¹-36⁶ weeks).

RESULTS

474,957 subjects with singleton gestations had data available to calculate the IPI. Of these, 1.4% (n = 6797) experienced PPROM. IPI ≤6 months was significantly associated with an increased risk of developing PPROM compared with patients with IPI ≥24 months (odds ratio (OR) 1.80, 95% CI 1.70-1.90, p < .001). A higher proportion of women with IPI ≤6 months delivered between 28¹ and 32⁰ weeks compared to the other two IPI groups (27.0 versus 15.0 and 16.4%, p < .001). Individual maternal factors associated with an increased risk of PPROM included advanced maternal age, African American race, BMI <18.5 kg/m², BMI ≥30 kg/m², use of social services, tobacco use, and a prior PTB.

CONCLUSION

Our data demonstrate that an IPI of ≤6 months is significantly associated with an increased risk of developing PPROM in the subsequent pregnancy. Of greater clinical relevance is that these women were more likely to deliver between 28¹ and 32⁰ weeks as compared with women with a longer IPI. Novel to this study is the establishment of a specific link between a short IPI and PPROM with subsequent early delivery. Several maternal demographic factors known to be associated with PTB risk were also found to be associated with an increased risk of PPROM. Further studies are necessary to elucidate plausible biologic mechanisms ultimately leading to the development and implementation of preventive and therapeutic strategies for this high-risk cohort.

Cervical collagen is reduced in non-pregnant women with a history of cervical insufficiency and a short cervix

INTRODUCTION

Preterm cervical shortening and cervical insufficiency may be caused by a constitutional weakness of the cervix. The aim of this study was to assess the cervical collagen concentration in non-pregnant women with a history of cervical insufficiency or of a short cervix in the second trimester of pregnancy.

MATERIAL AND METHODS

In this case-control study we included non-pregnant women one year or more after pregnancy: 55 controls with a history of normal delivery; 27 women with a history of cervical insufficiency; and 10 women with a history of a short cervix (<5th percentile) and 10 women with a history of a long cervix (>95th percentile) at gestational weeks 18-20. We obtained biopsies (3 × 3-4 mm) from the ectocervix and determined the collagen concentration by measuring the hydroxyproline concentration.

RESULTS

Women with cervical insufficiency had lower collagen concentrations (63.5 ± 5.1%; mean ± SD) compared with controls (68.2 ± 5.4%; p = 0.0004); area under the ROC curve 0.73 (95% CI 0.62-0.84). A cut-off value at 67.6% collagen resulted in a positive likelihood ratio of 3.2, a sensitivity of 60%, and a specificity of 81%. Also, women with a short cervix in the second trimester had lower collagen concentrations in a non-pregnant state (62.1% ± 4.9%) compared with women with a long cervix (67.8% ± 5.0%; p = 0.02).

CONCLUSIONS

Both cervical insufficiency and a short cervix in the second trimester of pregnancy are associated with low cervical collagen concentrations in a non-pregnant state more than one year after pregnancy.

Association between interpregnancy interval and the risk of recurrent loss after a midtrimester loss

STUDY QUESTION

After an initial midtrimester loss, is the interval to the next conception associated with the risk of a recurrent loss?

SUMMARY ANSWER

Among women who had a pregnancy loss at 14-19 weeks gestation, conception at least 3 months after this initial loss was associated with a reduced risk of a recurrent loss.

WHAT IS KNOWN ALREADY

A short interpregnancy interval (IPI) has been thought to increase risk but recent studies of pregnancy after a loss have found no effect; however, these studies have been based almost entirely on an initial first trimester (<14 weeks) loss.

STUDY DESIGN, SIZE, DURATION

A retrospective cohort study drawing on over 997 000 linked birth and hospital records from New South Wales, Australia for 2003-2011. Index pregnancies were those of women who had a first recorded pregnancy loss of 14-23 weeks gestation (miscarriage, termination and perinatal death). The study population was 4290 women who conceived again within 2 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The index loss was categorized by subgroups: 14-19 weeks gestation versus 20-23 weeks, and by whether spontaneous or a termination. The primary outcome was any loss or perinatal death before 24 weeks in the subsequent pregnancy.

MAIN RESULTS AND THE ROLE OF CHANCE

After a 14-19 weeks index loss, an IPI of ≤3 months had an increased rate of recurrent loss compared with an IPI of >9-12 months: 21.9% versus 11.3% (adjusted relative risk (aRR) = 2.02, 95% CI 1.44-2.83). For women who had a spontaneous index loss of 20-23 weeks, there was no evidence that a short IPI increased or decreased the risk of recurrent loss. For any gestational age group of index losses, an IPI of >18-24 months increased the risk of a recurrent loss; the risk was highest after a 20-23 weeks index loss (aRR = 2.15, 95% CI 1.18-3.91).

LIMITATIONS, REASONS FOR CAUTION

We do not know how many cycles were required to achieve conception. Pregnancies resulting in early first trimester losses are unlikely to have resulted in hospitalization so would not have been identified.

WIDER IMPLICATIONS OF THE FINDINGS

The risk of recurrent loss after an initial midtrimester loss may differ from the risk after an initial first trimester loss.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by an Australian National Health and Medical Research Council (NHMRC) Centre for Research Excellence Grant (1001066). C.L.R. is supported by an NHMRC Senior Research Fellowship (#APP1021025). J.B.F. is supported by an ARC Future Fellowship (#120100069). The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Cervical strain determined by ultrasound elastography and its association with spontaneous preterm delivery

OBJECTIVE

To determine if there is an association between cervical strain, evaluated using ultrasound elastography, and spontaneous preterm delivery (sPTD) <37 weeks of gestation.

METHODS

One hundred and eighty nine (189) women at 16-24 weeks of gestation were evaluated. Ultrasound elastography was used to estimate cervical strain in three anatomical planes: one mid-sagittal in the same plane used for cervical length measurement, and two cross sectional images: one at the level of the internal cervical os, and the other at the level of the external cervical os. In each plane, two regions of interest (endocervix and entire cervix) were examined; a total of six regions of interest were evaluated.

RESULTS

The prevalence of sPTD was 11% (21/189). Strain values from each of the six cervical regions correlated weakly with cervical length (from r=-0.24, P<0.001 to r=-0.03, P=0.69). Strain measurements obtained in a cross sectional view of the internal cervical os were significantly associated with sPTD. Women with strain values ≤25th centile in the endocervical canal (0.19) and in the entire cervix (0.14) were 80% less likely to have a sPTD than women with strain values >25th centile [endocervical: odds ratio (OR) 0.2; 95% confidence interval (CI), 0.03-0.96; entire cervix: OR 0.17; 95% CI, 0.03-0.9]. Additional adjustment for gestational age, race, smoking status, parity, maternal age, pre-pregnancy body mass index, and previous preterm delivery did not appreciably alter the magnitude or statistical significance of these associations. Strain values obtained from the external cervical os and from the sagittal view were not associated with sPTD.

CONCLUSION

Low strain values in the internal cervical os were associated with a significantly lower risk of spontaneous preterm delivery <37 weeks of gestation.

Vaginal progesterone vs. cervical cerclage for the prevention of preterm birth in women with a sonographic short cervix, previous preterm birth, and singleton gestation: a systematic review and indirect comparison metaanalysis

OBJECTIVE

No randomized controlled trial has compared vaginal progesterone and cervical cerclage directly for the prevention of preterm birth in women with a sonographic short cervix in the mid trimester, singleton gestation, and previous spontaneous preterm birth. We performed an indirect comparison of vaginal progesterone vs cerclage using placebo/no cerclage as the common comparator.

STUDY DESIGN

Adjusted indirect metaanalysis of randomized controlled trials.

RESULTS

Four studies that evaluated vaginal progesterone vs placebo (158 patients) and 5 studies that evaluated cerclage vs no cerclage (504 patients) were included. Both interventions were associated with a statistically significant reduction in the risk of preterm birth at <32 weeks of gestation and composite perinatal morbidity and mortality compared with placebo/no cerclage. Adjusted indirect metaanalyses did not show statistically significant differences between vaginal progesterone and cerclage in the reduction of preterm birth or adverse perinatal outcomes.

CONCLUSION

Based on state-of-the-art methods for indirect comparisons, either vaginal progesterone or cerclage are equally efficacious in the prevention of preterm birth in women with a sonographic short cervix in the mid trimester, singleton gestation, and previous preterm birth. Selection of the optimal treatment needs to consider adverse events, cost and patient/clinician preferences.